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darian

problem with LNAV, and IRS autopilot

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ok after i followed the PMDg 744 Normal Procedures manual step by step i cant get the LNAV autopilot to function right, nor the IRS nav display. After i go through checklist step by step, it comes to the point where you have to set the IRS mode select from OFF to NAV to ALIGN. I did that and my IRS is set to instant alignment. After the checklist ask to program IRS posistion in FMC I did that then it says switch the IRS mode back to NAV. When i do this the IRS display does not display the heading, distance to next waypoint, and if i switch it back to ATT is displays nothing. Then i have to keep going back and forth and it just wont work right. Finally on one flight I got the IRS to display hdgs, dis and the LNAV would not work. After i press LNAV it flicks on for a sec then off. I need you guys PMDG to respond quick. Oh the frames are better now but these things described above are unacceptable.

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Hi Darian,The manual gives erroneous instructions on how to initialize the IRS units. Here are the proper steps:1. Switch from "OFF" to "NAV" (do not move back to "ALIGN")2. When prompted by FMC (after 10 min., if using real world option for aligning), enter IRS POSITION from the POS INIT page LSK R4, and upselect it to LSK R5.I think this may help.Tomas

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Darian, first of all you might want to drop the 'I need you guys PMDG to respond quick' tone here. If you need immediate support use the support email address.Most of the support you will get here is from fellow users who do it on their own time, politeness goes a long way.With that out of the way, let's look at the IRS problem first.It will actually work if you set the IRU's directly to NAV and leave the ALIGN bit out. Once you've set them to NAV enter the co-ords in the FMC. If that doesn't work, you're missing a step in your startup procedures somewhere.LNAV should work fine, in order to see why it didn't for you we'd need to see the flightplan you were flying.Good luck!

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:( sorry i got the IRS display to properly display nav hdg distance and waypoints, but the LNAV still would not function right. When I press LEGS page on FMC to fly direct to waypoint it doesnt fly direct rather fly from starting AP to that waypoint. And even if i press LNAV it just flicks on for a split second then shuts off. I switched the IRS from OFF to NAV it did nothing, i waited for over 10minutes. Then i switched from OFF to NAV again entered IRS POS in FMC then the IRS displayed proper waypoints and dis. But no LNAV function. And my IRS I set for instant alignment, should it be set to 10 minutes just like real world or does it matter.I guess the main problem i have now is LNAV. If any of you have your PMDG 744 operating properly tell me your exact procedure PLEASE so I can start flying. My FP is this:KLAX SNGO5 MZB J1 TIJ UT4 LMM UJ3 GDL UJ7 UPN UJ3 ACA UL344 SLS UV1 LIM UL302 ARPON UL550 ROS UA558 MULTA UW24 SNT STAR SAEZ

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:-jumpy :-jumpy :-jumpy :-jumpy :-jumpy I GOT LNAV to work FINALLYi think its because i didnt have my departure airport runways programmed in the FMC. In the 737s you dont need to put in runways guess its different with the 747 but anyways thanks i can finally go fly this beautiful bird. Honestly I was getting to breaking point also.

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Glad you got it sorted out sorted out Darian, enjoy!Just left the flight deck 5 mins ago after nearly 16 hours in flight from KORD to VHHH - UA895. I was using the freeware VHHH scenery by Thomas Kwong for the first time (as recommended to me the other day). What a brilliantly done scenery, no frame rate hit either! Heading back to KSFO tomorrow.Time now for a beer, log my PIREP, have a review of the flight before catching a quick 'simpsons' episode then hitting the hay, I'm tired after only spending 3 hours away from the flight deck the whole flight!

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